Shoe with air cushion sole and method for manufacturing the shoe



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SHOE WITH ALR CUSHION SOLE AND METHOD FOR MANUFACTURING THE SHOE sheet Z ore INVENTOR.

June 3 1969 E. DRExLL-:R 3,447,251

SHOE WITH AIR CUSHION SOLE AND METHOD FOR MANUFACTURING THE SHOE Filed lay 1, 1967 sheet 3 of e IN VENTOR.

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June 3,` 1969 E. DREXLER 3,447,251v

SHOE'WITH AIR CUSHION SOLE AND METHOD FOR MANUFACTURING THE SHOE Filed my 1. 1967 sheet 5 of e l (1o/loa) 447 J INVENTOR.

June 3, 1969 E. DREXLER 3,447,251

SHOE WITH AIR SHI SOLE AND METHOD FOR )IANUF UR THE SHOE Filed may 1, 1967 sheet 6 or 'e I NVENTOR.

AT/rich aezler United States Patent i() SHOE WITH AIR CUSHION SOLE AND METHOD FOR MANUFACTURING THE SHOE Erich Drexler, Linsenpfad, 6719 Kirchheimbolanden, Pfalz, Germany Filed May 1, 1967, Ser. No. 635,158 Claims priority, application Germany, Apr. 30, 1966, St 25,319 Int. Cl. A43c 13/08 U.S. Cl. 36-14 24 `Claims ABSTRACT OF THE DISCLOSURE A shoe having an upper to which is attached a bottom comprised of a preformed sole held spaced from the bottom of the lasted upper by a spacer situated between the bottom of the lasted upper and sole. The spacer is located inwardly of the edge of the sole, a cushion layer lls the space between the bottom of the lasted upper and the sole inwardly of the spacer, and an attaching strip surrounds the edge of the sole, the adjacent shoulder of the lasted upper and lls the space between the bottom of the lasted upper and the sole outwardly of the spacer. Also a method of joining the preformed sole to the bottom of the lasted upper by holding it against a cushion layer of smaller size than the sole and with a spacer surrounding the cushion layer and forming a connecting strip around the edge of the sole and the adjacent shoulder of the lasted upper.

Background of the invention Shoes with air-cushion soles are well-known. A rising interest exists with buyers for shoes of this type in spite of the manufacture-conditioned diiculties as well as the relatively high price, since the wearing qualities of the shoes with air-cushion soles offer a considerable comfort for the feet. Up to now, shoes of this type with air-cushion sole were manufactured with more or less complicated sole and bottom construction. The disadvantage with the hitherto familiar constructions is above all that the production stipulates a high portion of manual labor.

The invention is concerned with the construction of shoes with air-cushion sole as well as form and process for their manufacture. The task at the basis of the invention is to simplify the construction and production of shoes with air-cushion sole, in such a way that the expenditure of manual labor with the production of shoes of this type is reduced.

Summary The invention consists in a special forming of a shoe with air-cushion sole, which according to the invention is connected to the upper by injecting a plasticizable synthetic material or rubber. According to the invention, it is provided that the air-cushion is arranged in the area of the sole or half sole which has been sealed against the injected material. Thereby, it is provided that with the injecting of the synthetic material or rubber, which produces the connection between the air-cushion sole and the upper, the sensitive air-cushion does not corne in contact with the injected material.

According to the process of the invention, shoes with air-cushion soles are produced by the fact that a premanufactured sole or half sole together with the air cushion are moved by a sole plate in the mold of an injection molding machine into engagement with a lasted upper whereupon an eXtrudable material capable of being injected into the mold cavity, in particular synthetic material or rubber, is injected into the mold cavity provided for this purpose between the sole and the upper to produce a joining.

Patented June 3, 1969 rice According to the invention, therefore, the air-cushion soles, consisting of a sole or half sole and air-cushion, are connected with the upper in an injection molding machine. Thereby, this essential part of the manufacturing process may be carried out by machine.

Preferably, according to the invention, the sole or half sole is made with the same sole plate with which the sole or half sole is moved together with the air-cushion into engagement with the upper.

A further proposal of the invention consists in the fact that the air-cushion is sealed by a sealing ring, separated from the sole or half sole, against the injected material.

The use according to the invention of a special sealing ring, which separates the air-cushion from the injected material, has various advantages. First of all a sole or half sole can be used, which is essentially free from elevations on the side confronting the upper or air-cushion. Therefore soles or half soles made in the usual manner can be used, especially also soles stamped out from sheets or the like. These soles can then be processed as customary soles, in particular roughened on the upper side and spread over with an adhesive agent. Thereby the costs for the production of the sole or half sole as well as the expenditure in handling of the same are reduced.

Also this method makes possible the use of different materials for the sole or half sole, on the one hand, and the sealing ring, on the other hand. The sole or half sole can consist of a material corresponding to the requirements of practice, for example, to be especially abrasionproof, oil-proof, heat-resistant, and the like. In comparison with this, the sealing ring can `be of a material of desirable elasticity and formability, for example, porous or cellular synthetic material or rubber.

It is also advantageous that by using a separate sealing ring the thickness of the manufactured air-cushion can be adapted better and more easily corresponding to the practical requirements at any given time through corresponding dimensioning of the sealing ring. With a sole or half sole with formed sealing lip, the thickness of the air-cushion sole is predetermined. To that extent, desirable adjustings are made possible without the use of a corresponding number of different molds for the production of soles or half soles.

It is further provided that the packing ring is fastened at the sole or half sole and/or at the upper or at the insole, especially by means of adhesive. This is also advantageous, since the sole or half sole and/or the upper extension or insole are provided in the usual manner with an adhesive agent which here can also serve for the fastening of the sealing ring.

According to another proposal of the nvention, the sealing ring can be injected to the upper or to the insole for which an injection mold made according to the invention is used.

The invention will now be described in greater detail with reference to the accompanying drawings wherein:

FIG. 1 shows a shoe with air-cushion sole during the manufacturing according to the invention in schematic longitudinal section;

FIG. 2 shows a cross-section lI-II of FIG. 1;

FIG. 3 shows a half sole according to the invention in top View;

FIG. 4 shows a sole or half sole with air cushion in schematic cross-section;

FIG. 5 shows another form of method of the sole or half sole, likewise in cross-section;

FIG. `6 shows a third form of method of the sole or half sole, likewise in cross-section;

FIG. 7 shows another form of method of the invention in a representation corresponding to FIG. 1;

FIG. 8 shows a form for Athe production of a sole or half sole in schematic cross-section;

FIG. 9 shows a variant of the form according to FIG. 8;

FIG. 10 shows a longitudinal section of an injection mold for the production of a half sole;

FIG. 11 shows a shoe according to the invention with an injection mold form in schematic cross-section;

FIG. 12 shows another form of method of a shoe according to the invention in a cross-section corresponding to FIG. 11; and

FIG. 13 shows a formed part for the production of van injected sealing ring according to the invention in crosssection.

The invention is concerned with .the production of shoes with air-cushion soles. The air-cushion sole as illustrated herein is comprised of a premanufactured sole 10 (FIG. 1) or half sole 10a (FIG. 7). The sole 10 can consist of a material suitable for the purpose of use of the shoes, for example, a material which is resistant to wear, heat, and solvents such as oil, benzene, and the like. A chey figuur-rubber mixture is especially suitable. The term chemigu-m being employed to identify the series of nonstaining, oil-resistant, vulcanizable, synthetic rubbers of the butadiene acrylonitrile type. The sole 10 can, however, also have other properties.

The air-cushion sole also consists of an air cushion 11, which can be arranged either over substantially the entire bottom surface of the shoe (FIG. 1) or only in lthe area of the half sole 10a (FIG. 7).

This air-cushion sole constructed in this manner and consisting of the sole 10 or half sole 10a and the air-cushion 11 is joined according to the invention by means of `an injection hold 12 to the upper 13 of the shoe.

For lthis purpose, the upper 13, preferably with an insole 14, is drawn on a last 15. The injection mold comprises -a sole plate 16 which is movable with a side rin-g 17, preferably divided into two parts, on whose sealing lip 18 the last 15 with the upper 13 thereon is set.

To produce `the connection between the air cushion sole 10, 11 and the upper 13, according to the invention, a suitable material, prefer-ably synthetic material or rubber, is Iinjected into the mold cavity. The sole 10 or half sole 10a is provided for this purpose, as shown, with an adhesive layer 19 along its marginal edge, which projects into a space running all around the mold 12 for receiving an edge strip 20. In the example shown in FIG. 1, the sole 10 and air-cushion 11 are provided throughout the area of Athe shank 22 and heel 21. The air-cushion sole 10, 11 is joined to the upper by injection of the edge strip into the mold cavity to ll the space surrounding the aircushion sole 10, 11.

According to the invention, the sole 10 or half sole 10a is premanufactured, for example, by vulcanizing. Then this sole 10 or half sole 10a with the air-cushion 11 is raised by the sole plate 16 in the side ring 17 against the bottom of the last 15 on which the upper -is mounted or against the insole if an insole is provided. Preferably the surface of the upper 13 and the insole 14 which come in contact with the air-cushion sole and the edge strip, 20, as well as the marginal edge of the sole 10 or halfsole 10a, are roughened and spread with an adhesive agent. Then the material of the edge strip is injected. For ithis purpose the side ring 17 (FIG. l) is provided with injection passages 23 and 23a and the sole plate is provided with injection passages 24 and 25. The injection passages 23 and 24 provide injection through the sole plate. The passages 2S extend to the sole edge and guarantee a distribution of the material for the forming 'of the edge strip 20 all the way around the peripheral edge of the bottom. The injection of the material into the cavity surrounding the sole to form the edge strip 20 can be carried out in various ways. For example, as shown in FIGS. 1 and 2, the passages 25 are connected to the nace into which the edge is to be injected through holes 26 or cut out places 27 in the marginal edge of the sole 10. This provides for fast distribution of the material.

In the form shown in FIG. 7, wherein the helf sole 10a and air-cushion 11 are connected -to the upper 13, the injection passage 24 is connected to the interior of the mold cavity by a passage 28. An additional passage 29 is provided in the area of the heel. In this manner, rthe edge strip 20 and shank can be injected simultaneously, `and the holes 26 and cut-outs 27 are not necessary. By providing the passages 28 and 29 the passage 29a may -be omitted so that no sprue is visible at the heel end.

According to the invention, the air-cushion 11 is so arranged in the area of the sole that the material for the formation of the edge strip 20, as Well as according to FIG. 7, the shank 22 and the heel 21a, does not come into contact with the sensitive air-cushion. For this purpose, on the side of the sole 10 or the half sole 10a, confronting the upper 13, a sealing lip 30 is provided which runs all around. The lip 30 encloses the air-cushion 11 and when pressed against the underside of the upper and/ or insole forms a seal which prevents the injected material from penetrating the air-cushion 11. The sealing lip 30 is formed in a special manner, and indeed is provided at the inner side, confronting the air-cushion 11, with a stabilizing thickening 31 and at the outer side, confronting the edge strip 20, with a groove 32. As thus formed, the sealing lip 30 is bent outwardly as it is pressed into engagement with the upper 13 thereby insuring the sealing elfect.

In FIGS. 4 to 6 various modied forms of soles 10 or half soles 10a with an air-cushion 11 are shown in crosssection. With all of the forms a reinforcement 33 of the sole 10 or half sole 10a is provided preferably in the form of a sealing lip 30, since it has been found that the greatest abrasion and wear takes place at the junction of the elastic cushion area of the air-cushion sole with the compact edge part. The adhesive-coated marginal edge 19 of the sole 10 or half sole 10a can drop ot at an angle outwardly (FIG. 5 run horizontally (FIG. 4), or run off at an acute angle (FIG. 6). For the injecting of the edge strip 20, as shown in FIG. 5, the sole 10 or half sole 10a can be smaller in the cross-section measurements than the finished air-cushion sole 10 or 10a, 11 and 20. In this case, holes 26 and cut-out places 27 in the sole 10 or 10a can be done away with, since the material of the edge strip 20 can be injected laterally together with the edges of the sole 10 or half sole 10a.

According to the invention, the sole 10 or half sole 10a is preferably prepared -by the same sole plate 16 with which the sole 10 or half sole 10a, together with the aircushion 11, are moved toward the last 15. Trimming of the sole 10 or half sole 10a is accordingly not necessary. moreover, by providing the sole plate with a suitably engraved surface the tread surface of the sole or half sole may be embossed simultaneously with its formation.

In FIG. 8 in schematic cross-section a mold for the production of the sole 10 or half sole 10a is shown. This mold has a sole plate 16 and a side ring 34 which preferably contains a groove 35 running al1 around, so that when the vulcanized sole cools and contracts the finished sole corresponds exactly to the dimensions which are desired. A top plate 36 is used in place of the last 15 for making the sole 10 and has a surface 36a confronting the sole plate 16 corresponding to the upper surface of the sole and also cut-out places for the formation of the sealing lip 30. The top plate 36 and side ring 34 are interchanged after the making of the sole with the last 15 and the side ring 17 for the making of the shoe.

In FIG. 9 is represented a modification of the mold shown in FIG. 8. The sole 10 or half sole 10a can be produced in this mold (FIG. 9) by vulcanization in a vulcanizing press. For this reason, the mold construction deviates from that of FIG. 8. The mold according to FIG. 9 consists of a top plate 36 and a bottom plate 41, the latter having a side wall 41a integral therewith.

FIG. shows a longitudinal section of an injection mold for the producing of a half sole 10a. The mold has a top part 39 and a bottom part 37. An injection passage 38 is provided which naturally also can lie differently than indicated. The injection mold according to FIG. 10 provides a mold cavity for a half sole 10a which has an edge part 40a sloping downwardly so that the portion of the half sole at the shank end is bent downwardly. This is especially advantageous for Ibottom-forming with the mold shown in FIG. 7, since the downwardly bent portion at the rear end of the half sole 10a will be pressed rmly against the sole plate 16 and thus prevent ow of the injected material beneath the half sole 10a.

The molds according to FIGS. 9 and 10 show distinctly that the sole 10 or half sole 10a for the shoe, according to the invention, can be made by a vulcanization process, that is in vulcanizing presses, as well as by an injection process.

In FIGS. 11 to 13, according to the invention, there is a separate sealing ring 45 or 48 running all around. This is manufactured as a separate element of suitable, preferably elastic, material. In the form shown in FIG. 11 the sealing ring 45 is cut from an extruded or otherwise formed length of material which has the contours of the sole 10 or half sole 10a.

The sealing ring 45 is preferably joined to the upper 13 or to an inturned extension 13a of the upper and/or t0 the sole 10, preferably by means of adhesive. For this, no additional processing is necessary since the upper extension 13a as well as the insole 14 and also the upper side of the sole 10 are already spread with an adhesive agent as related above, which here can serve at the same time for the fastening of the sealing ring 45.

The sealing ring 45 consists preferably of porous or cellulosic synthetic material or rubber. Thereby, the sealing ring 45 can tit especially tight against the upper surface of the sole 10 and the lower surface of the upper 13. To increase the sealing effect, the sealing ring 45 has a concave outer edge which, according to FIG. 1l, provides sealing edges 46 and 47 for engagement with the inner edge of the edge strip 20.

In the form shown in FIG. 12, the separation or sealing between the air-cushion 11 andthe edge strip 20 is effected by a downturned prolongation 45a of the .extension 13a. The prolongation 45a is in the form of a lasting margin which runs all the way around the bottom. For the reinforcement or supporting of the prolongation 45a, according to the invention, a support 48 is provided which runs all the way around and is preferably triangular in crosssection.

The sealing ring 45, according to the invention, can also be made and fastened by molding, especially by injection to the upper 13 or to the extension 13a or to the insole 14.

In FIG. 13 is shown partially an injection mold by means of which the sealing ring 45 running all the way around is applied to the upper extension prior to attaching the sole. For this purpose, a special mold plate 49 is provided, which has a groove 50 running all around to receive the material for the sealing ring 45. The mold plate 49 can, by way of example, be set on the sole plate 16 of the injection mold during the producing of the sealing ring 45. It is also possible to provide a special plate for this purpose. The mold plate 49 contains at least one injection passage in communication with the groove 50.

The production of a shoe with air-cushion soles proceeds with a mold according to PIG. 13 in the manner that first the sealing ring 45 is' injected, then the aircushion 11 with the sole 10 or half sole 10a is pressed into engagements with the upper 13 and/or the sealing ring 45, and nally the edge strip 20 is injected.

The sealing ring 45 can be made thicker than the aircushion 11 so as to project below the lower surface of the air-cushion 11, so that movement of the sole 10 into engagement therewith will be sufficient to eect sealing.

The invention can also be used with shoes without an upper extension, for example, with so-called moccasin shoes.

It should be understood that the present disclosure is for the purpose of illustration only and that this invention includes all modifications and equivalents falling within the scope of the appended claims.

I claim:

1. In a shoe, an upper and a composite bottom comprising a sole corresponding susbtantially in size to the bottom of the lasted upper, a cushion layer of smaller size than the bottom of the lasted upper interposed between the bottom of the lasted upper and the sole, and a connecting strip joining the peripheral edge face of the sole to the lateral surface of the upper at the shoulder; characterized in that there is a spacer situated between the bottom of the lasted upper and the upper surface of the sole, said spacer being located inwardly from the edge face of the sole and providing at its outer side in conjunction with the bottom surface of the upper and the upper surface of the insole outwardly thereof an outwardly open groove, and its inner side in conjunction with the bottom of the lasted upper and the upper surface of said sole inwardly thereof a cavity within which the cushion layer is confined, and said connecting strip embodying a laterally extending rib situated within said outwardly facing groove and adhesively joining the lower surface of the upper and the upper surface of the sole outwardly of the spacer.

2. A shoe according to claim 1, wherein the sole is performed by vulcanization and the spacer is formed integral therewith during formation.

3. A shoe according to claim 1, wherein the spacer is upwardly tapering in cross-section having a broad base and converging sides, the inner one of which is substantially at and the outer one of which is re-entrant.

4. A shoe 4according to claim 1, wherein the spacer is upwardly tapering in cross-section and slopes outwardly toward the edge of the sole.

5. A shoe according to claim 1, wherein the sole contains one or more openings at its marginal edge outwardly of the spacer and the material of the connecting strip extends into and lls these openings.

6. A shoe according to claim 1, wherein a reinforcement is applied to the area of the spacer confronting the cushion layer.

7. A shoe according to claim 1, wherein the portion of the sole outwardly of the spacer is substantially uniformly thick and has a substantially horizontal upper surface.

8. A shoe according to claim 1, wherein the portion of the sole outwardly of the spacer tapers and has an outwardly sloping upper surface.

9. A shoe according to claim 1, wherein the spacer is comprised of a material other than that of the sole, for example porous or cellulose synthetic material or rubber.

10. A shoe according to claim 1, wherein the spacer is connected to the upper by means of adhesive.

11. A shoe according to claim 1, wherein the spacer is connected to the upper by means of adhesive.

12. A shoe according to claim 1, wherein the spacer is connected to the insole by means of adhesive.

13. A shoe according to claim 1, wherein the spacer has at least one outwardly extending sealing edge preferably adjacent the sole.

14. A shoe according to claim 1, wherein the spacer has outwardly extending sealing edges adjacent the sole and bottom of the lasted upper or insole.

15. A shoe according to claim 1, wherein the lasting margin of the upper extends downwardly from the bottom about the peripheral edge of the cushion layer and constitutes the spacer.

16. A shoe according to claim 1, wherein the lasting margin of the upper extends downwardly from the insole at the bottom of the upper about the peripheral edge of the cushion layer and constitutes the spacer separating the cushion layer from the connecting strip.

17. A shoe according to claim 1, wherein the spacer has an uncompressed thickness which is greater than the thickness of the cushion layer.

18. A shoe according to claim 1, wherein adhesive is applied to the surface portions of the upper, cushion layer, sole, connecting strip and rib having mutual contact.

19. A shoe according to claim 1, wherein the composite bottom comprises a whole sole including a portion of the shank and heel and the cushion layer is substantially coextensive therewith.

20. The method of making shoes with cushion soles comprising providing a mold containing a mold cavity having a re-entrant groove peripherally thereof, supporting a lasted upper at the top of the mold cavity and a preformed sole at the bottom in spaced relation thereto with a spacer engaged between them, said spacer being located inwardly of the edge of the sole and with a cushion sole situated between the bottom of the lasted upper and sole within said spacer, and injecting a plasticized body of material into the mold cavity around the edge of the sole and the adjacent shoulder of the upper and into the space between the bottom of the lasted upper and the top of the sole outwardly of the spacer.

21. A method according to claim 20, comprising forming openings in the marginal edge of the sole outwardly of the sealing lip and then forming the connecting strip by injecting the plasticized material through said openings to enhance the joining of the sole to the upper.

22. The method according to claim 20, comprising providing the sole with an upwardly tapering sealing strip 8 which by contact with the bottom of the lasted upper prevents the plasticized material from reaching the peripheral edge of the cushion layer.

23. The method according to claim 20, comprising bending the lasting margin downwardly from the insole to provide a sealing strip for engagement with the sole peripherally of the cushion layer.

24. The method according to claim 20, comprising providing a reinforcing strip of triangular cross-section and placing it between the downturned lasting margin and the peripheral edge of the cushion layer.

References Cited I UNITED STATES PATENTS 1,562,040 11/ 1925 Oakley 36-32 2,129,106 9/1938 Szerenyi et al. 2,363,456 11/1944 Wright. 2,481,389 9/1949 Campagna 36-14 3,066,426 12/ 1962 Strickland. 3,185,752 5/ 1965 Bingham. 3,305,895 2/1967 Ludwig 264-244 X 3,319,301 5/1967 Ludwig 264-244 X FOREIGN PATENTS 1,392,836 2/1965 France.

882,341 11/1961 Great Britain.

ALFRED R. GUEST, Primary Examiner.

U.S. Cl. X.R. 18-42; 264-244 

